diff --git a/types/commonmark/commonmark-tests.ts b/types/commonmark/commonmark-tests.ts
index b85eb16ace..25ceac5695 100644
--- a/types/commonmark/commonmark-tests.ts
+++ b/types/commonmark/commonmark-tests.ts
@@ -36,7 +36,13 @@ const xmlRenderer = new commonmark.XmlRenderer({ sourcepos: true, time: true });
 const xml = xmlRenderer.render(node);
 console.log(xml);
 
-const htmlRenderer = new commonmark.HtmlRenderer({ safe: true, smart: true, sourcepos: true, time: true });
+const htmlRenderer = new commonmark.HtmlRenderer({
+    safe: true,
+    smart: true,
+    sourcepos: true,
+    time: true,
+    softbreak: "<br/>",
+ });
 const html = htmlRenderer.render(node);
 console.log(html);
 
diff --git a/types/commonmark/index.d.ts b/types/commonmark/index.d.ts
index 7ceb1fd2c5..0f9c0f70a0 100644
--- a/types/commonmark/index.d.ts
+++ b/types/commonmark/index.d.ts
@@ -216,6 +216,12 @@ export interface HtmlRenderingOptions extends XmlRenderingOptions {
      *  if true, source position information for block-level elements will be rendered in the data-sourcepos attribute (for HTML) or the sourcepos attribute (for XML).
      */
     sourcepos?: boolean;
+
+    /**
+     * A raw string to be used for a softbreak.
+     * For example, `{ softbreak: "<br/>" }` treats a softbreak as `<br/>`.
+     */
+    softbreak?: string;
 }
 
 export interface XmlRenderingOptions {